Massive integration of distributed energy resources has resulted in a demand for miniaturized power conversion circuits (e.g., inverter topologies, etc.) with minimal requirements for filtering elements. Switching converters rely on the switching between multiple modes of operation to generate a desired output. Conventional power electronic converters utilize semiconductor switches to generate a voltage pattern to be filtered by inductors and capacitors. Although these conventional switching converters are simple and require a low number of components, they output large ripples. To reduce the ripples, bulky inductors and capacitors are required.
Conventionally, ripples induced in switching converters are filtered using LC or LCL filters. Although this method of filtering switching ripples is effective and low cost, it cannot provide ripple-free voltage and current signals. Additionally, if low ripple outputs are of interest, the size of the converter will increase due to the requirements for larger filtering elements. Unlike traditional applications, modern power converters are expected to be small, low cost, and offer lighter weights while maintaining low input/output ripples and high efficiency.
Another challenge with conventional switching converters is the utilization of electrolyte capacitors. These capacitors are the first cause of failure in switching converters. An average life span of an industrial grade electrolyte capacitor is 5 to 7 years. However, the remaining circuit components, including the semiconductor switches, offer more than 30 years of life expectancy on average. Hence, systems (e.g., solar energy systems, etc.) including conventional switching converters that utilize electrolyte capacitors have their expected life spans reduced to less than 10 years, which can jeopardize the return-on-investment analysis. Hence, power conversion circuits with minimal filtering capacitors are of interest.